Which of the following is not a natural contraceptive method ?

Options

A. Periodic abstinence
B. Coitus interruptus
C. Lactational amenorrhea
D. M.T.P.

Answer

To determine which of the following is not a natural contraceptive method, we will analyze each option provided.

1. **Periodic Abstinence**: This method involves avoiding sexual intercourse during the fertile period of a woman's menstrual cycle, specifically a few days before and after ovulation (typically days 10 to 17). By doing this, the chances of sperm meeting an egg are significantly reduced. Therefore, periodic abstinence is considered a natural contraceptive method.

2. **Coitus Interruptus**: Also known as the withdrawal method, this involves the male partner withdrawing the penis from the vagina before ejaculation. This method aims to prevent sperm from entering the female reproductive tract, thus reducing the chances of conception. Coitus interruptus is also classified as a natural contraceptive method.

3. **Lactational Amenorrhea**: This method refers to the natural infertility that occurs when a woman is exclusively breastfeeding. During the first six months postpartum, a woman typically does not menstruate, which significantly lowers the chances of ovulation and conception. Hence, lactational amenorrhea is recognized as a natural contraceptive method.

4. **MTP (Medical Termination of Pregnancy)**: This refers to the medical procedure for terminating a pregnancy, commonly known as abortion. MTP is not a method of contraception; rather, it is a procedure that occurs after conception has already taken place. Therefore, it is not classified as a natural contraceptive method.

Based on this analysis, the answer to the question "Which of the following is not a natural contraceptive method?" is **MTP (Medical Termination of Pregnancy)**.

### Final Answer:
**MTP (Medical Termination of Pregnancy)** is not a natural contraceptive method.